1. Field of the Invention
This invention relates to electrically conductive oxides having a single phase cubic KSbO.sub.3 -type crystal structure. The KSbO.sub.3 structure is readily identifiable by characteristic x-ray reflections and has been described in the art [e.g. P. Spiegelberg, Arkiv Kemi, 14A (5), 1 (1940)].
2. Description of the Prior Art
Some oxides corresponding to the general formulas shown below have frequently been found in the past to have the pyrochlore-type structure. Such pyrochlore structures are characterized by variable compositions expressed by the formulation (Na,Ca).sub.2 (Nb,Ti).sub.2 (O,F).sub.7 and are well known in the art. While the pyrochlore-type structure is cubic, it is face-centered cubic in contrast to either the primitive or body-centered cubic characteristic of the cubic KSbO.sub.3 structure. Additionally, x-ray determinations show the pyrochlore structure to have a lattice constant (a.sub.o) greater than 10A whereas the lattice constant for the cubic KSbO.sub.3 -type structure of the present compositions is considerably less than 10A.
In Journal of Research or National Bureau of Standards 75, 385 (1971), McDaniel and Schneider list 2SrO-3IrO.sub.2 as one of the compounds in the Sr-IrO.sub.2 phase system in air. It is described as cubic, with the KSbO.sub.3, structure, but was not prepared as a single phase, therefore, the exact composition is not known.